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Actinomycetes are able to utilize a great variety of carbohydrates, like sugar. The particular kind of sugar and its concentration has decisive effect on the growth of microorganisms. The proper nutritional media aids also in the production of spores. Based on this generalization, that the growth and sporulation of microorganisms are greatly influenced by the nature and the concentration of carbohydrates, an attempt has been made to study Actinoplanes philippinensis with respect to this influence. digital.library.unt.edu/ark:/67531/metadc163928/

This investigation has been made with reference to the adaptability of Andropogon ischaemum, King Ranch bluestem, to various soils, various slopes, and various erosion conditions in Denton County. digital.library.unt.edu/ark:/67531/metadc96951/

This study is another phase of the overall research program designed to furnish basic information for the management of East Texas lakes and has as its specific purpose the determination of the age and growth characteristics of two valuable species on these waters. The species to be considered are the black crappie, Pomoxis nigro-maculatus (Le Sueur) and the white crappie, Pomoxis annularis Rafinesque. Both species are highly regarded as food fish and have for many years offered recreational outlets for Texas fishermen. digital.library.unt.edu/ark:/67531/metadc75663/

This study was made to secure certain new information concerning the food habits and growth of the white bass, Lepibema chrysops (Rafinesque), which is quite generally considered a good game and good fish. digital.library.unt.edu/ark:/67531/metadc53380/

This study is based on the examinations and analyses of 388 largemouthed black bass (Micropterus salmoides) and 118 spotted black bass (Micropterus puctulatus ssp.) which were collected over a period of three years from 9 lakes in the North-Central and East Texas areas. The results should show the following: (1) the average age of the black bass in each of the nine reservoirs in Texas; (2) the growth rate of the bass in these reservoirs; (3) the feeding habits of the bass in all reservoirs studied; (4) a comparison of the growth rates of the largemouthed and spotted basses; and (5) a comparison of the growth rates of bass from Texas and Oklahoma. digital.library.unt.edu/ark:/67531/metadc96895/

This investigation was planned to observe if the leukemic thymic tissue in vitro would inactivate TSH and to study the effect that TSH would have on the leukemogenic properties of these cells when transplanted into a high-leukemia strain of mice. digital.library.unt.edu/ark:/67531/metadc107887/

The purpose of this study is to determine the status of elementary science curricula in the different state universities and the leading teachers colleges in the United States. digital.library.unt.edu/ark:/67531/metadc75584/

The purpose of this investigation was to analyze the distribution of amphibians and reptiles in Texas by means of the methods of Webb and Hagmeier and Stults. An additional graphical analysis was made, including range and range limits which provides a cross-section of faunal change along selected base lines across the state. digital.library.unt.edu/ark:/67531/metadc131149/

Canonical correspondence analysis (CCA) was used to explore relationships between measured environmental variables and in situ phytoplankton communities in a moderately eutrophic North Texas Reservoir. digital.library.unt.edu/ark:/67531/metadc278929/

This syllabus includes both lecture notes and laboratory activities for a two-semester anatomy and physiology community college course. The syllabus is based on a 16-week semester that is comprised of a three-hour lecture section and a one-hour laboratory class each week. Both the lecture course and laboratory are necessary to fulfill the requirement for anatomy and physiology. Laboratory activities coincide with lectures to enhance understanding of each topic by providing visual and hands-on experiments for the concepts learned in the lecture. Laboratory quizzes will be given each week to help students maintain a working knowledge of the material learned in the laboratory. This course is appropriate for the typical anatomy and physiology student and should benefit both students who plan to major in biology and also those who are non-biology majors. Because subject matter in anatomy and physiology is quite difficult, the importance of attendance and good study skills is stressed. digital.library.unt.edu/ark:/67531/metadc2500/

This investigation deals with the study of the possible antibiotic effect of oleoresins of one hundred common Texas plants upon twenty-five gram-negative bacterial organisms. digital.library.unt.edu/ark:/67531/metadc83529/

This investigation is concerned with the testing, in vitro, of oleoresins from one hundred higher plants common to North and South Central Texas. The plants used were selected in order to obtain a representative collection which might be of value in future research. digital.library.unt.edu/ark:/67531/metadc96860/

This problem has been concerned with, first, the collection of sixteen species of plants belonging to Cactaceae family; second, the drying of these and the extraction of the oleoresins thereof; third, the determination of the extent to which these substances inhibit the growth of ten gram-positive and ten gram-negative bacterial organisms; and fourth, a determination of the possible utilization of these extracts a prophylactic or chemotherapeutic agents. digital.library.unt.edu/ark:/67531/metadc97010/

This thesis attempts, first, to correlate pigmentation of actinomycetes with the degree of antibiocity; second, to establish the most favorable means of producing a rich luxuriant pigmentation in the individual organism studied by enriching favorable media with specific types of proteins and amino acids. digital.library.unt.edu/ark:/67531/metadc96995/

The purpose of this problem is to determine the presence and extent of antibiotic materials as found in the oleoresins of a selected group of garden vegetables. The problem has consisted of, first, the collection and preparation of specimens of twenty-five commonly used garden vegetables; second, the extraction of the oleoresins from these; third, the determination of the inhibitory and other effects of these oleoresins against several strains of selected gram-positive and gram-negative bacteria; and fourth, the evaluation of the potentialities of these oleoresins with regard to their future use as medicinal prophylactics and therapeutics. digital.library.unt.edu/ark:/67531/metadc96958/

This problem was undertaken to determine the potentialities of chlorine dioxide as an algaecide and as an agent for the removal of tastes and odors from fresh water. digital.library.unt.edu/ark:/67531/metadc107825/

This particular work is proposed as a test of the expedience of using the fluorescent-antibody technique as a method for enumeration and identification of certain strains of B. cereus that have been found to be effective in preventing taste and odor in water supplies resulting from certain Actinomycete blooms. digital.library.unt.edu/ark:/67531/metadc163949/

It was the purpose of this investigation to present laboratory data concerning the assimilation of inorganic nitrogen by the aquatic actinomycetes. The strains of aquatic actinomycetes under consideration represented a cross section of those currently under culture at North Texas State University. digital.library.unt.edu/ark:/67531/metadc108150/

There were two purposes of this investigation: the first was to develop a method for studying spore germination, hyphal growth and mycelial development of the aquatic actinomycetes under the microscope so that the life cycle of this organism could be continuously followed. The second purpose was to determine the rate of carbon utilization from various types of nutritional sources, and to correlate this with the colony development and spore formation. digital.library.unt.edu/ark:/67531/metadc163851/

This thesis describes the present nature of one facet of some of the flood plain forest stands in Denton County, Texas. The specific purpose was to demonstrate the presence or absence of difference between the Celtis laevigata (commonly known as the hackberry, southern hackberry or sugarberry) populations in stands on Denton Creek and Elm Fork of the Trinity River. digital.library.unt.edu/ark:/67531/metadc163960/

The purpose of this investigation is to determine if auto-antibodies are demonstrable in inflammatory periodontal disease using methods other than those of Novotny. digital.library.unt.edu/ark:/67531/metadc108240/

The purpose of this investigation is to add to the present day knowledge concerning the presence of antibiotics in additional members of the spermatophyte group of plants. digital.library.unt.edu/ark:/67531/metadc83741/

This thesis is an investigation of Antibiotic "S" with the purpose of determining which organisms it has a marked effect on, the amount required to cause inhibition, its action in blood, and its therapeutic effect and toxicity in laboratory animals. digital.library.unt.edu/ark:/67531/metadc83589/

This thesis aimed to study the seventy-two representative wells of Denton County and to determine the possibilities of infection with typhoid organism. The sanitary survey and the test for Colon-Aerogenes bacteria show that 55% of the 72 wells studied are unsanitary, 27% are sanitary, and 18% are doubtful. digital.library.unt.edu/ark:/67531/metadc29851/

The problem of this thesis consists of a bacterial analysis of twenty-five representative wells within a radius of thirty miles of Canyon, Texas. An attempt has been made to determine the possible presence of the typhoid organism in these wells. digital.library.unt.edu/ark:/67531/metadc75367/

A bacterial analysis of the water from thirty-six sources of consumption by the white population of Trinidad, Henderson County, Texas, was made to determine the potability of each of these in regard to infection from typhoid or related organisms. digital.library.unt.edu/ark:/67531/metadc75382/

In this study organisms that can be subcultured from lake water, using a prescribed procedure, limit, to an extent, the population, or portions of the population, that can be monitored. In essence, what is taking place is that a set of conditions is set forth and a study is made of the bacteria that will grow under these prescribed conditions. digital.library.unt.edu/ark:/67531/metadc130924/

The purpose of this investigation is to compare the dissolved and suspended organic material in Lake Dallas to that coming into the lake through Pecan Creek. digital.library.unt.edu/ark:/67531/metadc75591/

Federal regulations such as the Clean Water Act (P.L. 92-500), and its amendments, direct the Environment Protection Agency (EPA) to implement programs to control the releases of conventional pollutants and toxics into the waterways of the United States. The EPA began requiring treatment plants to conduct toxicity tests (biomonitoring) of their effluent discharges. To control toxicity caused by chlorination of wastewater discharges, the EPA also began requiring some treatment facilities to dechlorinate their wastewater before discharging. This research was funded by the EPA to document the changes that occurred in the Trinity River from the dechlorination of the effluent from Ft. Worth's Village Creek municipal wastewater treatment plant. The study occurred over a two year period beginning in August 1990. A wide variety of biological field assessments and toxicological assays were used to measure various responses. Seven river stations, covering approximately twenty river miles, and the treatment plant effluent were assessed. Two of the river stations were upstream from the treatment plant and used as reference sites. The remaining five river stations were downstream from the treatment plant, spread out over seventeen river miles. The study evaluated the impact of chlorination prior to dechlorination, which served as a baseline. Responses determined during dechlorination were compared to the baseline data. An overall improvement in species richness and diversity was seen at those river stations which had previously been adversely impacted by chlorine. Aquatic toxicity tests, such as those required to be used by dischargers, were conducted during this study. Periodic toxicity was observed with these tests in the effluent and river samples after dechlorination was initiated. Those tests, along with in situ toxicity assays, proved to be good predictors of biological community responses. digital.library.unt.edu/ark:/67531/metadc279074/

The removal of phenols from the waste waters of wood preserving plants has always presented problems. The purpose of this paper is to investigate the possibility of employing a biological system to reduce the phenol content of effluent from these plants. digital.library.unt.edu/ark:/67531/metadc131445/

A thorough biological survey and evaluation is a lengthy and expensive project. The number of technically trained persons required prevent its use by most public agencies. Since public health departments are the groups most frequently concerned with measuring the effects of pollution in streams, a need exists for a simplified method of sanitary survey. Recognizing this need, the Texas Heal Department assigned the writer the problem of devising a method of survey which would require a field party of two and could be conducted entirely from a mobile field laboratory. digital.library.unt.edu/ark:/67531/metadc130298/

A life history study of Callibaetis floridanus was conducted over the wet cycle of a playa on the Southern High Plains of Texas from June through September 1995. digital.library.unt.edu/ark:/67531/metadc277876/

The purpose of this investigation was to study the effects of decreased barometric pressure on the transcapillary movement of molecules by monitoring the macromolecular capillary permeability with lymph derived primarily from the hepatic and gastrointestinal regions of the dog. digital.library.unt.edu/ark:/67531/metadc131162/

In view of its varied concepts and interpretations, and because of the discrepancies produced by the previous utilization of polydispersed dextrans, a study using extremely narrow-range molecular weight dextran fractions was initiated to reevaluate and consolidate some of the aspects of capillary permeability. A portion of the study was performed under decreased barometric pressure in order to clarify further some of the mechanisms involved in particulate transfer across the capillary endothelial membranes. Gel filtration procedures augmented the study as an assessment of the polydispersity effects of the dextrans employed. digital.library.unt.edu/ark:/67531/metadc164035/

Brucella ovis is a sexually transmitted, facultatively anaerobic, intracellular bacterial pathogen of sheep (Ovis aries) and red deer (Cervus elaphus). Brucella spp. infect primarily by penetrating the mucosa and are phagocytized by host macrophages, where survival and replication occurs. At least in some species, it has been shown that entry into stationary phase is necessary for successful infection. Brucella, like other alphaproteobacteria, lack the canonical stationary phase sigma factor ?s. Research on diverse members of this large phylogenetic group indicate the widespread presence of a conserved four-gene set including an alternative ECF sigma factor, an anti-sigma factor, a response regulator (RR), and a histidine kinase (HK). The first description of the system was made in Methylobacterium extorquens where the RR, named PhyR, was found to regulate the sigma factor activity by sequestering the anti-sigma factor in a process termed "sigma factor mimicry." These systems have been associated with various types of extracellular stress responses in a number of environmental bacteria. I hypothesized that homologous genetic sequences (Bov_1604-1607), which are similarly found among all Brucella species, may regulate survival functions during pathogenesis. To further explore the involvement of this system to conditions analogous to those occurring during infection, pure cultures of B. ovis cells were subjected to environments of pH (5 and 7) for 15, 30, and 45 minutes and oxidative (50mM H2O2) stress, or Spermine NONOate for 60 minutes. RNA was extracted and converted to cDNA andchanges in transcript levels of the sigma factor Bov1605 were measured using qPCR. Preliminary results indicate that under the exposure to Spermine NONOate there was little change in expression, but under oxidative stress expression of the sigma factor Bov1605 was 4.68-fold higher than that expressed under normal conditions. These results suggest that the sigma factor Bov1605 may be involved in oxidative stress defense during infection. Under acid stress (pH5), Bov1605 was found to be upregulated at 15 and 30 minutes, but after 45 and 60 minutes the time decreased. digital.library.unt.edu/ark:/67531/metadc177218/

This thesis describes an experiment involving guinea pigs' blood and the changes that occurred in the serum with the injection of an antigen. The serum was analyzed in complement titration tests. digital.library.unt.edu/ark:/67531/metadc107964/

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Aspartate transcarbamoylase (ATCase) catalyzes the first committed step in the pyrimidine biosynthetic pathway. Bacterial ATCases have been divided into three classes, class A, B, and C, based on their molecular weight, holoenzyme architecture, and enzyme kinetics. Moraxella bovis is a fastidious organism, the etiologic agent of infectious bovine keratoconjunctivitis (IBK). The M. bovis ATCase was purified and characterized for the first time. It is a class A enzyme with a molecular mass of 480 to 520 kDa. It has a pH optimum of 9.5 and is stable at high temperatures. The ATCase holoenzyme is inhibited by CTP > ATP > UTP. The Km for aspartate is 1.8 mM and the Vmax 1.04 µmol per min, where the Km for carbamoylphosphate is 1.05 mM and the Vmax 1.74 µmol per min. digital.library.unt.edu/ark:/67531/metadc3012/

An aspartate transcarbamoylase (ATCase) gene from Bordetella pertussis was amplified by PCR and ligated into pT-ADV for expression in Escherichia coli. This particular ATCase (pyrB) was an inactive gene found adjacent to an inactive dihydroorotase (DHOase) gene (pyrC'). This experiment was undertaken to determine whether this pyrB gene was capable of expression alone or if it was capable of expression only when cotransformed with a functional pyrC'. When transformed into E. coli TB2 pyrB-, the gene did not produce any ATCase activity. The gene was then co-transformed into E. coli TB2 pyrB- along with a plasmid containing the pyrC' gene from Pseudomonas aeruginosa and assayed for ATCase activity. Negative results were again recorded. digital.library.unt.edu/ark:/67531/metadc3057/

The present study of the production and properties of an antibiotic was undertaken in the hope that some useful information could be contributed to a long-range investigation program being carried on at North Texas State Teachers College. This program is concerned with the production of a useful antibiotic from a variant of the Penicillium notatum-chysogenum group of molds. digital.library.unt.edu/ark:/67531/metadc70386/

The purpose of this problem was to determine the cause of tastes and odors in the Breckenridge water supply and to isolate and culture the organisms responsible for the offensive chemicals. digital.library.unt.edu/ark:/67531/metadc97004/

The effect of excess gravity on bone-forming elements of the growing perichondrial shaft of embryonic chicks was investigated through the use of the transmission electron microscope and various cytochemical techniques. digital.library.unt.edu/ark:/67531/metadc131630/

It was the purpose of the present investigation to demonstrate the selection of a variant of one strain of Staphylococcus aureus by altering certain environmental factors, and to study that variant as to biochemical activities and capsule formation. digital.library.unt.edu/ark:/67531/metadc108202/

The primary purpose of this investigation is not only to improve the present technique of culture of Mycobacterium tuberculosis, but also to make a comparative study of the media use, namely, Veterans Administration modification of Trudeau's medium, Lowenstein's egg medium, and that developed by the author, in order to find which, if any, of these will most easily and effectively meet the needs of the hospital laboratory. digital.library.unt.edu/ark:/67531/metadc83506/

This study was made in an effort first, to determine the mode of transmission of the inheritance of a predisposition to cancer as revealed through the analyses of four separate human genealogies, and second, to make a comparative study of the genealogies to determine whether the mode of transmission is the same. digital.library.unt.edu/ark:/67531/metadc75283/